Hydrosilylation of cinchonidine and 9-O-TMS-cinchonidine with triethoxysilane: application of 11-(triethoxysilyl)-10,11-dihydrocinchonidine as a chiral modifier in the enantioselective hydrogenation of 1-phenylpropane-1,2-dione

A1 Journal article (refereed)


Internal Authors/Editors


Publication Details

List of Authors: Lindholm A, Maki-Arvela P, Toukoniitty E, Pakkanen TA, Hirvi JT, Salmi T, Murzin DY, Sjoholm R, Leino R
Publisher: ROYAL SOC CHEMISTRY
Publication year: 2002
Journal: Journal of the Chemical Society, Perkin Transactions 1
Journal acronym: J CHEM SOC PERK T 1
Issue number: 23
Start page: 2605
End page: 2612
Number of pages: 8
ISSN: 1472-7781


Abstract

The detailed synthesis and characterization of (-)-11-(triethoxysilyl)-10,11-dihydrocinchonidine (4), a starting material for the immobilization of (-)- cinchonidine on silica based supports, is described. Compound 4 together with its precursors 9-O-(trimethylsilyl)cinchonidine (2) and 9-O-(trimethylsilyl)-11-(triethoxysilyl)-10,11-dihydrocinchonidine (3) were employed as chiral modifiers in the hydrogenation of a prochiral diketone, 1-phenylpropane-1,2-dione, over a heterogeneous Pt/Al2O3 catalyst using cinchonidine (1) as a reference modifier. The unexpected enhancement of ee induced by 4, demonstrating the positive effect of distal modifier substitution, is discussed in the light of molecular modeling and NMR studies.

Last updated on 2019-18-07 at 06:48